1. Technical Field
The present invention relates to an array substrate, and more particularly, to an array substrate having a gate driving circuit with an improved output characteristic and a display apparatus having the same.
2. Discussion of the Related Art
A liquid crystal display is one of the most widely used flat panel displays. For example, a liquid crystal display is commonly found in a variety of electronic devices such as flat screen televisions, laptop computers, cell phones and digital cameras.
In general, a liquid crystal display includes a display panel that displays an image in response to a gate signal and a data signal, a gate driving circuit that outputs the gate signal and a data driving circuit that outputs the data signal.
The display panel includes an array substrate on which a plurality of gate lines for receiving the gate signal and a plurality of data lines for receiving the data signal are formed, a color filter substrate facing the array substrate and a liquid crystal layer disposed between the array substrate and the color filter substrate.
The gate driving circuit and the data driving circuit are typically mounted on the liquid crystal display panel. Recently, however, the gate driving circuit has been formed on the array substrate to reduce the size of the liquid crystal display and enhance its productivity.
When the gate driving circuit is formed on the array substrate, the gate driving circuit includes a shift register having a cascade connection. Each of the stages includes a plurality of transistors and a plurality of capacitors.
The capacitors are connected to an output terminal of the shift register to ensure that the gate signal outputted from the shift register has a sufficient rise time. Thus, when a charging capacity of the capacitors is insufficient, the rise time is shortened, thereby deteriorating the output characteristic of the gate driving circuit.
In one technique for enhancing the charging capacity of the capacitors, an electrode area of the capacitors is increased. This, however, causes an increase in the parasitic capacitance that exists between the capacitor electrode and a common electrode of the color filter substrate.
As such, a need exists for an array substrate that includes capacitors having an enhanced charging capacity for reducing the deterioration of the output characteristic of a gate driving circuit.